package com.laoxu.java.collection;

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;

/**
 * @author laoxu
 * @create 2018-01-31
 **/
public class HashMapExample {
    public static void main(String args[]) {

      /* This is how to declare HashMap */
        HashMap<Integer, String> hmap = new HashMap<Integer, String>();

      /*Adding elements to HashMap*/
        hmap.put(12, "Chaitanya");
        hmap.put(2, "Rahul");
        hmap.put(7, "Singh");
        hmap.put(49, "Ajeet");
        hmap.put(3, "Anuj");

      /* Display content using Iterator*/
        Set set = hmap.entrySet();
        Iterator iterator = set.iterator();
        while(iterator.hasNext()) {
            Map.Entry mentry = (Map.Entry)iterator.next();
            System.out.print("key is: "+ mentry.getKey() + " & Value is: ");
            System.out.println(mentry.getValue());
        }

      /* Get values based on key*/
        String var= hmap.get(2);
        System.out.println("Value at index 2 is: "+var);

      /* Remove values based on key*/
        hmap.remove(3);
        System.out.println("Map key and values after removal:");
        Set set2 = hmap.entrySet();
        Iterator iterator2 = set2.iterator();
        while(iterator2.hasNext()) {
            Map.Entry mentry2 = (Map.Entry)iterator2.next();
            System.out.print("Key is: "+mentry2.getKey() + " & Value is: ");
            System.out.println(mentry2.getValue());
        }

    }
}
